diff --git a/src/js/editor/editor.js b/src/js/editor/editor.js
index aaf2ff07d..513ed6367 100644
--- a/src/js/editor/editor.js
+++ b/src/js/editor/editor.js
@@ -648,9 +648,9 @@ class Editor {
         this.handleNewline(event);
         break;
       case key.isPrintable():
-        let { range } = this;
+        range = this.range;
         let { isCollapsed } = range;
-        let nextPosition = range.head;
+        nextPosition = range.head;
 
         if (this.handleExpansion(event)) {
           event.preventDefault();
diff --git a/src/js/editor/key-commands.js b/src/js/editor/key-commands.js
index 52e3a9a2d..057b1d540 100644
--- a/src/js/editor/key-commands.js
+++ b/src/js/editor/key-commands.js
@@ -3,6 +3,7 @@ import { MODIFIERS, SPECIAL_KEYS } from '../utils/key';
 import { filter, reduce } from '../utils/array-utils';
 import assert from '../utils/assert';
 import Range from '../utils/cursor/range';
+import Browser from '../utils/browser';
 
 export const DEFAULT_KEY_COMMANDS = [{
   str: 'META+B',
@@ -53,9 +54,11 @@ export const DEFAULT_KEY_COMMANDS = [{
     });
   }
 }, {
-  // FIXME restrict to OS X only?
   str: 'CTRL+A',
   run(editor) {
+    if (!Browser.isMac) {
+      return false;
+    }
     let range = editor.cursor.offsets;
     let {head: {section}} = range;
     editor.run(postEditor => {
@@ -63,9 +66,11 @@ export const DEFAULT_KEY_COMMANDS = [{
     });
   }
 }, {
-  // FIXME restrict to OS X only?
   str: 'CTRL+E',
   run(editor) {
+    if (!Browser.isMac) {
+      return false;
+    }
     let range = editor.cursor.offsets;
     let {tail: {section}} = range;
     editor.run(postEditor => {
diff --git a/src/js/utils/browser.js b/src/js/utils/browser.js
new file mode 100644
index 000000000..653d9a92a
--- /dev/null
+++ b/src/js/utils/browser.js
@@ -0,0 +1,3 @@
+export default {
+  isMac: /Mac/.test(navigator.platform)
+};